Reinforced metal tube



July 11, 1939. H p NQRDMARK I 2,165,294

REINFORCED METAL TUBE Filed Jan. 23, 1937 MM j my pozxziziizwflggw w /R g ATTORNEYS.

Patented July 11, 1939 PATENT OFFHCE REINFORCED METAL TUBE Henry P. Nordmark, Grand Rapids, Mich., assignor to American Seating Company, Grand Rapids, Mich., a corporation of New Jersey Application January 23, 1937, Serial No. 121,946

1 Claim.

The present invention relates to reinforced 7 metal tubes and more particularly to means for reinforcing seams of metal tubes in their assembled relation with pivotally or rigidly connected 5 and associated parts.

Illustrative embodiments of the invention are shown in the accompanying drawing, wherein:

Figure 1 is a sectional view on line l-| of Figure 3 of a reinforced tube and its rigidly secured transverse rod; Figure 2 is a sectional view thereof on line 2-2 of Figure 3; v

Figure 3 is a sectional view on lines 3-3 of Figures 1 and 2;

Figure 4 is a sectional view on line 4-4 of Figure 5 of a reinforced tube and itsipivotally connected link;

Figure 5 is an el-evational view thereof;

Figure 6 is a sectional view of a reinforced tube having neither a rigidly nor a pivotally connected.

member associated therewith;

Figure 7 is an elevational view of a reinforced tube and its bifurcated arm supporting cap secured at one end thereof;

Figure 8 is a top plan view thereof; and

Figure 9 is a sectional view on line 9--9 of Figure 7.

Referring to the drawing in which like parts of a metal tube and its longitudinal seam reinforcing mechanically equivalent elements are designated by the same numerals in the several views, the metal tube I0, is here shown as triangularly form-ed in cross-section from sheet metal stock whose longitudinal lengths I l are folded inwardly to provde a finished seam l2;

Means for reinforcing the seam l2 comprises a ferrule 13 straddling the seam and embracing a pin M which is projected through the seam and which pierces the wall of the tube opposite the seam thereof.

,In Figures 1-3 of the drawing, the pin [4 has a head [5 in engagement with the outer wall of the tube, the other end 16 of the pin being enlarged to provide a shoulder ll in engagement with the ferrule. In these views, a rod may be thus rigidly secured to the tube transversely thereof whose seam is thus reinforced by the ferrule I3.

In Figures 4 and 5, the head l5 of the pin is in engagement with the outer wall of the tube l and its enlarged portion I6 forming a shoulder ll bears against the ferrule l3. A pivotal connection between the tube l0, whose'seam I2 is thus reinforced, is provided by the link I8 disposed between the ferrule l3 and the head IQ of the pin Hi.

In Figure 6 of the drawing, the seam [2 of the tube In is merely reinforced by the ferrule l3 which embraces the pin l4 whereas in Figures 7-9, the double ferrule I3 has a head portion 26 forming a cap secured to one end of the tube ill by the pin I4. The cap which is here shown as provided with bifurcated arms 2| thus doubly reinforces the seam l2 of the tube It].

Although the means herein shown for reinforcing the longitudinal seams of metal tubes in their assembled relation with pivotally or rigidly connected and associated parts is particularly well adapted for use in connection with the economical manufacture of folding chairs, it will be obvious to those skilled in the art that this reinforcing means is applicable in conjunction with other manufacturing operations wherein metal tubes having longitudinal finishing seams are employed.

While but several embodiments of the invention have been herein shown and described, it will be understood that certain details of the constructions shown may be altered or omitted without departing from the spirit of this invention as the same is defined by the following claim.

I claim:

a Means for reinforcing the longitudinal seam of a metal tube comprising a pin projected through the seam of the tube and-piercing the opposite wall thereof, and a ferrule straddling saidseam and embracing the pin, one end of said pin having a shoulder in engagement with said ferrule and the other end of the pin being riveted over into engagement with the outer wall of said tube.

HENRY P. NORDMARK. 

